Do fundal polyps found during endoscopy (esophagogastroduodenoscopy) require a biopsy?

Fundic Gland Polyps and Biopsy Requirements

Fundic gland polyps (FGPs) should be biopsied when there is diagnostic uncertainty based on endoscopic appearance, but typical-appearing FGPs can be managed without routine biopsy in most cases. 1

When Biopsy IS Recommended

Biopsy confirmation should be sought when in doubt about the diagnosis. 1 Specifically, biopsy or excision is indicated for:

• Atypical features: Size >1 cm, antral location, ulceration, or unusual appearance that questions the diagnosis of FGP 1
• Dysplastic-appearing polyps: Where typical surface and vascular architecture is altered, particularly when irregular 1
• Suspected FAP: Large numbers of polyps (>20), young age (<40 years), or presence of duodenal adenomas 1
• Initial diagnosis confirmation: To establish histological diagnosis and exclude dysplasia when FGPs are first encountered 1

When Biopsy May NOT Be Required

The 2019 British Society of Gastroenterology guidelines acknowledge that diagnosis of FGPs is easily made from endoscopic appearance 1. Research supports this, showing that typical endoscopic features predict FGPs with 89.3% accuracy 2.

Typical endoscopic features of FGPs include:

• Multiple, small (<1 cm) polyps located in fundus and corpus 1
• Pale, smooth, glassy, transparent or translucent appearance 1
• Color lighter than or same as surrounding mucosa 1
• Lacy blood vessels visible through translucent surface 1
• Fine grey dot pattern on surface 1

Practical Algorithm

For typical-appearing FGPs:

1. Document number, location, morphology, and size of largest polyp 1
2. Take representative photographs 1
3. If appearance is classic and polyps are <1 cm in fundus/corpus, biopsy may be deferred 2
4. However, the 2017 BSG/AUGIS guidelines recommend biopsies to confirm histological diagnosis and exclude dysplasia (strong recommendation, moderate evidence) 1

For atypical features, biopsy or excise:

• Any polyp >1 cm 1
• Polyps in antral location 1
• Ulcerated or irregular appearance 1
• When multiple polyps present, representative biopsies are sufficient as coexisting polyps are usually the same histological type 1

Critical Caveats

Risk of dysplasia/malignancy in FGPs is low but not zero: Larger FGPs (>1 cm) have been shown to be dysplastic in 1.9% and contain focal cancer in 1.9% 1. This risk justifies the strong guideline recommendation for biopsy confirmation 1.

FAP context changes management: In FAP patients, microscopic adenomatous foci within FGPs occur in 44.4% of cases 3, and gastric adenomas can be difficult to differentiate from FGPs 4. These patients require more aggressive biopsy strategies 4.

PPI use: FGPs are associated with long-term PPI use and can spontaneously regress when PPIs are stopped 1. Re-evaluate PPI appropriateness in all patients with FGPs 1.

No surveillance needed: There is no role for surveillance gastroscopy for typical FGPs, except in FAP patients 1.